• 동아시아식생활학회지
• /
• 제25권5호
• /
• pp.842-849
• /
• 2015

The purpose of this study was to determine the optimal mixing ratio of hot-air dried loquat leaf powder and optimum conditions for making Jeolpyun containing hot-air dried loquat leaf powder (LLP). Samples of Jeolpyun were prepared with different contents of hot-air dried LLP (0%, 3%, 6%, 9%, 12%) followed by analysis of chemical properties, moisture contents, color, mechanical quality characteristics, amylograph, and sensory tests. Chemical analysis showed that hot-air dried LLP consisted of 11.41% water, 8.34% crude protein, 1.90% crude fat, 7.74% crude ash, and 16.95% crude fiber, with $^{\circ}Brix$ of 2.07, and pH of 5.78. Moisture contents of samples ranged from 52.22 to 50.06%. L-value decreased with addition of hot-air dried LLP, whereas a-value increased with increasing amount of hot-air dried LLP, and no significant differences were observed regarding b-value. In the mechanical evaluation of physical properties, hardness deceased with increasing amount of hot-air dried LLP. The starting temperature amylograph of Jeolpyun was higher in samples with hot-air dried LLP than those without hot-air dried LLP. Set back was slower with increasing amount of hot-air dried LLP, an increasing amount of hot-air dried LLP made set back of Jeolpyun slower. In the sensory test, Jeolpyun with 6% hot-air dried LLP was the most preferred with less bitterness and proper softness, moisture and chewiness. Therefore, addition of 6% hot-air dried LLP to Jeolpyun made with rice flour showed the best overall preference. Based on the results of this experiment, samples with hot-air dried LLP showed slower hardening than those without hot-air dried LLP in textural changes during storage, and Jeolpyun with 6% hot-air dried LLP is expected to increase quality and preference of Jeolpyun.

• 한국산학기술학회논문지
• /
• 제16권12호
• /
• pp.8363-8369
• /
• 2015

본 연구에서는 고유동 콘크리트에서 일라이트 미분말을 대체한 콘크리트의 유동성과 충전성 및 압축강도 특성을 조사하기 위한 것이다. 이러한 목적으로 일라이트 미분말을 고유동 콘크리트에 5, 10, 15, 20%를 대체한 후 치환율에 따른 콘크리트의 특성을 알아보았다. 콘크리트 배합 후 굳지않은 콘크리트에서 슬럼프 플로우 시험, 500mm플로우 도달시간 및 O-lot 시험을 실시하였으며, 굳은 콘크리트의 특성으로 재령 28일에 고유동 콘크리트의 압축강도를 측정하였다. 시험결과 고유동 콘크리트의 유동성 및 충전 높이는 일라이트 미분말 10%를 대체하였을 때까지 증가하는 것으로 나타났다. 그리고 고유동 콘크리트의 압축강도 특성을 살펴본 결과에서도 일라이트 미분말 10%를 대체하였을 때까지 강도증진이 발생하였다. 따라서 본 실험결과 일라이트 미분말의 혼입율이 10%일 때 최적 치환율이 되었음을 확인할 수 있었다.

• 한국환경복원기술학회지
• /
• 제2권2호
• /
• pp.43-52
• /
• 1999

This study was carried out to verify results of the nursery seedbeds. From November of 1997 to September of 1998, the artificial banking slopes in the greenhouse of the College of Agriculture and Life Sciences, Seoul National University were seeded with the mixtures of those species. Most of exotic species showed relatively poor development of root as short as 30cm. Also the green weight of root biomass of the native species was more than two times than that of the exotic species. On the other hand, it was found that the exotic species have relatively well-developed fine roots. Thus, it was concluded that the seed-mixture of the native species with long and thick roots and the exotic species with fine roots be the most effective method for topsoil erosion control on banking-slopes. The artificial rainfall system treatment(30mm/hr, 60mm/hr, 100mm/hr) on $30^{\circ}$ banking-slopes did not cause any significant change in the amount of soil loss by erosion. The root system was best developed in the plot of 1,000 seedlings per square meter and it performed well for soil erosion control. Consequently, in the case of seeding of single herbaceous species without mixing any woody seeds, the expected seedlings were 1,000 to 2,000 per square meter.

• 대한핵의학회지
• /
• 제27권2호
• /
• pp.270-276
• /
• 1993

$Technetium-^{99m}$ labeling method using bifunctional chelating agent cyclic DTPA has been evaluated with human polyclonal nonspecific IgG. IgG was conjugated with cyclic DTPA with various molar ratio. Reduction of $^{99m}Tc$ was done with $Na_2S_2O_4$ with various molar excess. Labeling efficiency and identification of polymer was confirmed with HPLC using TSK4000 SW column. Polymer was purified with 100 cm Sepharose 6LB column. Cultured $1{\times}10^9$ Staphylococcus aureus were injected into rat thigh 24 hours later labeled IgG was injected, and in vivo distribution was observed 4 and 24 hours thereafter. Reduction of $^{99m}Tc$ was optimal with the 10000-50000 times molar excess of $Na_2S_2O_4$. Polymer formation increased with increasing mloar excess of cyclic DTPA to IgG. Three step labeling-labeling DTPA conjugated IgG after reduction of $^{99m}Tc$-made more polymer than two two step labeling-simultaneous mixing DTPA conjugated IgG, $^{99m}Tc$ and $Na_2S_2O_4$. $^{99m}Tc$ blood clearance and lower uptake in the abscess and other organs. IgG conjugated with 200 times molar excess of cyclic DTPA showed slower blood clearance with 200 times molar excess of cyclic DTPA showed slower blood clearance than that of 200 times molar excess of cyclic DTPA showed slower blood clearance than that of 20 times molar excess. In the $^{99m}Tc$ labeling of IgG with cyclic DTPA for the immunoscintigraphy, obtimal labeling condition should be chosen, and effect of the $^{99m}Tc$ labeled IgG polymer should be considered.

• 한국응용과학기술학회지
• /
• 제35권3호
• /
• pp.683-694
• /
• 2018

인삼과립차의 편의성 및 기호성 증진을 위해 부형제인 젖당, 포도당 및 아라비안 검의 첨가량에 따른 과립차의 물리적 특성을 분석하였다. 젖당의 첨가량이 증가할수록, 포도당의 첨가량이 감소할수록 흡습성은 낮아지고 용해성은 증가하는 경향을 보였다. 사포닌 용출량은 첨가되는 부형제의 종류 및 양에 영향을 받기 보다는 인삼농축액의 첨가량에 더 큰 영향을 받는 것으로 나타났다. 아라비아 검의 첨가량이 증가할수록 흡습성, 용해성은 증가하는 경향을 보였고, 색도는 큰 차이점이 없었다. 부형제 첨가에 따른 인삼과립차의 최적 배합비는 인삼농축액 10%, 젖당 80%, 글루코즈 5% 그리고 아라비아 검의 함량이 5% 이었다.

• Journal of Microbiology and Biotechnology
• /
• 제17권7호
• /
• pp.1071-1078
• /
• 2007

Using a 50-1 airlift bioreactor, for the effective production of tylosin from Streptomyces fradiae TM-224 using raw cornmeal as the energy source, various environmental factors were studied in flask cultures. The maximum tylosin concentration was obtained at $32^{\circ}C$ and pH between 7.0 and 7.5. When seed was inoculated after 24 h of culture, the maximum tylosin concentration, 5.7 g/l, was obtained after 4 days of culture. Various concentrations of raw cornmeal were tested to investigate the optimum initial concentration for the tylosin production. An initial raw cornmeal concentration of 80 g/l gave the highest tylosin concentration, 5.8 g/l, after 5 days of culture. Of the various nitrogen sources, soybean meal and fish meal were found to be the most effective for the production of tylosin. In particular, with the optimal mixing ratio, 12 g/l of soybean meal to 14 g/l of fish meal, 7.2 g/l of tylosin was obtained after 5 days of culture. To compare raw cornmeal and glucose for the production of tylosin in the 50-1 airlift bioreactor for 10 days, fed-batch cultures were carried out under the optimum culture conditions. When raw com meal was used as the energy source, the tylosin production increased with increasing culture time. The maximum tylosin concentration after 10 days of culture was 13.5 g/l, with a product yield from raw cornmeal of 0.123 g/g of consumed carbon source, which was about 7.2 times higher than that obtained when glucose was used as the carbon source.

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2009년도 제33회 추계학술대회논문집
• /
• pp.627-630
• /
• 2009

이젝터 시스템은 주유동 제트에 발생되는 전단 응력과 압력차에 의해 흡입 챔버 압력에 영향을 미치거나 이차 흡입 유동을 유도한다. 이젝터는 터빈 기반 복합사이클 추진기관 및 로켓엔진의 고고도 모사 설비, 압력회복장치, 담수화 시스템, 이젝터 램젯시스템과 같이 많은 분야에 적용되어 널리 사용된다. 본 연구에서는 아음속 및 음속 조건에서 작동하는 이젝터의 형상 및 운전 조건을 결정하는 설계 절차를 수립하고자 하였다. 또한, 이론적 방법과 시험적 연구를 통해 축소 확대 디퓨저가 장착된 이젝터의 작동 특성을 파악하였다. 결국, 수치해석을 통해 요구 성능을 만족하는 이젝터의 최적 형상을 결정하였으며 다양한 노즐 목 및 챔버 직경을 변화시킨 이젝터에 대한 성능 시험을 통해 계산 결과를 검증하였다.

• 한국공작기계학회논문집
• /
• 제18권2호
• /
• pp.194-200
• /
• 2009

The extruder type is classified as screw type and non-screw type in terms of the extrusion method. The screw type extruder, which is the most frequently used, is classified as the single screw extruder and the multi-screw extruder. They are classified as vertical type and horizontal type in terms of structure; and those for compounding and for forming in terms of function. The single screw extruder is a universal extruder, most of which is suitable for the extrusion forming of thermoplastic resin. The multi-screw(two-screw, three-screw and four-screw) extruder can increase the extrusion power using the engagement of the screw flank. The single screw extruder does not have a good mixing ratio of the raw material and stable extrusion power, while it has low construction cost and operation cost. In this study, the single screw extruder, which has many weak points compared with the multi-screw extruder, was studied. There have been many studies on the single screw extruder, and they led to its significant development. The existing study method, however, had complex analysis processes and required much time. In this study, the CFD was applied to the performance test and analysis of the extruder, and the optimal design condition of the extrusion power for the screw and die of the single screw extruder was found by comparing the analysis results with the actual performance measurement of the single screw extruder.

• 한국환경복원기술학회지
• /
• 제2권4호
• /
• pp.64-73
• /
• 1999

This study was conducted to find out the effects of hydroseeding material and seed mixture on the revegetation of rock cut-slopes by PEC4 (Polymer-Ecology-Control) Hydroseeding Measures. PEC4 hydroseeding material was applied to four cut-slopes using hydroseeding measures from April to August, 1999, and the field survey was carried out by monthly. PEC4 material consisted of bark compost and organic soil amendments. This material has high content of organic matter and high level of water holding capacity. PEC4 hydroseeding material shows low level of soil hardness, so it gives to good condition for seed germinating and plant growing in early stage. PEC4 material attached at rock cut-slopes by two types of adhesive agent was not eroded by rainfall. The plant coverage and number of plant species were affected by mixing ratio of seeds and seeding timing. From the viewpoint of plant establishment, the optimal hydroseeding timing of mixed seeds for plant growth seems to be in May. Most of the plant seeds were germinated well and they covered rock cut-slopes so quickly and effectively. Plant importance value of Silene armeria and Platycodon grandiflorum. were higher than any other seeded-native species in the competition between native species and exotic species, so they have enough possibility to be used for slope revegetation works. Thus it leads to conclusion that the revegetation method used in this experiment was a very effective method for plant establishment on rock cut-slopes.

• 공업화학
• /
• 제25권4호
• /
• pp.409-413
• /
• 2014

폐아스팔트를 적정 처리하여 KS F 2572 규격을 만족하는 아스팔트용 순환골재를 회수한 후 신골재와 결합재(수분+유화아스팔트+에멀젼계 재생첨가제)의 최적의 혼합비율을 설계하여 현장 시공규격에 맞는 재활용 상온아스콘 혼합물을 생산하고자 하였다. 결합재의 최적 혼합비율 결정을 위한 실험 결과 수분함량이 증가함에 따라 전단강도는 감소하였으며, 수분함량이 3.0 wt%일 때 마샬안정도가 최대값을 보였다. 두 결과를 토대로 최적 수분함량은 3.0 wt%로 설정하였다. 또한 유화아스팔트의 함량에 따른 마샬안정도와 흐름치는 첨가량 0.5~2.5 wt%의 범위에서 모두 기준에 만족하였고, 공극률은 0.7~2.5 wt%의 범위에서 만족하였으므로 최적 첨가량은 공통으로 만족된 범위인 0.7~2.5 wt%의 가운데 지점인 1.6 wt%로 설정하였다. 재활용 상온아스콘 혼합물용 결합재의 최적 에멀젼계 첨가제 함량은 재활용 상온아스콘 혼합물의 마샬안정도와 포화도를 고려하여 0.1 wt%로 설정하였다.